Thought suppression failures in combat PTSD: a cognitive load hypothesis.

Department of Psychiatry, Yale University, New Haven, CT 06511, USA.
Behaviour Research and Therapy (Impact Factor: 3.85). 10/2009; 47(9):744-51. DOI: 10.1016/j.brat.2009.06.006
Source: PubMed

ABSTRACT The present study investigated the relation between thought suppression of emotionally neutral content [i.e., Wegner's (1994) "white bear"], incidental traumatic thought intrusion, and skin conductance responses in combat-related Posttraumatic Stress Disorder (PTSD). Participants included service members who either: a) had PTSD following an Operation Iraqi Freedom deployment; b) were free of psychiatric diagnosis following deployment (Combat Equivalent), or c) were pre-deployed and without psychiatric diagnosis (Pre-Deployed). PTSD Service Members reported the greatest intrusion of combat thoughts during the suppression task and demonstrated a post-suppression rebound effect with a neutral thought. Non-specific skin conductance responses indicated that the suppression task was related to similar levels of increased sympathetic activity for both the PTSD and Pre-Deployed groups, whereas the Combat Equivalent group showed no increased activation during thought suppression. Intrusive traumatic thoughts combined with failures in neutral thought suppression may be a consequence of increased cognitive load in PTSD.

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